noun
eyelid margin; edge of the eyelid
Anatomical term referring to the rim of the eyelid where the eyelashes grow.
目縁に小さなできものができた。
A small bump formed on the edge of my eyelid.
まつげは目縁から生えている。
Eyelashes grow from the eyelid margin.
まぶた means 'eyelid' as a whole, while まぶち refers specifically to the rim or edge of the eyelid.
Compound of 目 (me, 'eye') and 縁 (fuchi, 'edge, rim'), with rendaku voicing of ふち to ぶち. The reading まぶち is a straightforward combination.